The invention relates to a machine for profile working of front surfaces on oblong wood workpieces, and is preferentially a machine to produce toothed or wedge joints on front surfaces of oblong wood workpieces of various lengths and intersections for their later series joining, wherein the entrance and exit turnover device and oblique roller conveyor are integrated, while the conveying chain of adjacent longitudinal conveyors is equipped with movable clamping units.
According to the international patent classification this invention belongs to B 27F 1/12, and additionally to B 27F 1/16, B 65 G 17/46, and to B 65G 47/22.
There are quite some known solutions of machines or devices respectively for manufacturing of front surface toothed, wedge joints for series joining of oblong workpieces. According to the oldest known solution the wood workpieces move towards the working unit lineally, in their longitudinal axis direction, they are stopped in front of the working unit and clamped in the clamping device. Thereby, they are placed in the lying position on one of their larger surfaces. Thus clamped, the workpieces then proceed their way through or against, along the vertical or horizontal movable milling working unit, by which we first work one and then another front surface of workpieces, whereby they remain inside the fixed clamping device in the same position.
With another known oldest solution to make profile front surfaces, several workpieces are simultaneously collected by the side guiding lath just before the working unit. There follows activating of the clamping device that simultaneously clamps several workpieces together. Clamped workpieces are then front surface worked, first at one end in the way that the working unit moves lineally along the front surface straightened and steady workpieces. After working, the clamping device is liberated and workpieces proceed their way lineally forward, whereby they are front surface straightened by means of the adjacent conveyer on the opposite, not yet worked end, likewise by means of the side guiding lath. Their clamping and front surfaces working on the other end operations are repeated.
Weakness and deficiency of both previously described oldest known solutions are predominantly in the fact that front surface working of wood workpieces is progressed inside working, interactively interrupted strokes, what entails the working capacity limitation on the machine, as working strokes by themselves define the number of workings in a time unit. It is further also evident that they do not make any accurate positioning or a larger number of workpieces inside the clamping device before and during clamping front surface adjustment feasible, what inevitably causes inaccuracy of profile front surface working, and therewith intolerable discrepancy or aeration inside the built up toothed joint, what entails in not quality finished toothed joints on front surfaces, and the product built up of glued workpieces greater or smaller curvature. Both solutions are also impractical, as they are exclusively applicable for profile working of smaller intersections wood workpieces front surfaces, and do not make such working of workpieces larger intersections feasible.
Pursuant to the Slovenian patent SI 9700042, and pursuant to the European patent EP 0 870 584, the solution of the machine for making toothed or wedge joints in oblong workpieces front surfaces, constructed of the line entrance conveyer, rotating working construction, and line exit conveyer is known. The working construction is constructed in the lying roll form or a rotating drum respectively with the multiple basic surface having clamped units with auxiliary conveyers and adjacent working units placed on the periphery. Workpieces are individually transmitted from the entrance conveyer in the adjacent clamping unit area, which they rigidly clamp them and further circularly convey them passing by working units, and by lagging behind they work each workpiece front surfaces by cutting toothed radial form grooves in them. This known solution weakness and deficiency are above all in the complex and very demanding construction, the capacity of which is limited due to the circular working mode, as well as in the workpieces unreliable transverse shift among working units.
The next known solution is pursuant to the German patent DE 41 09 188, whereby workpieces are one upon another or in a package piled on the horizontal plate that shifts over the rotating axis to an oblique position and lifts the entire package of workpieces into the area of the adjacent working unit. There follows front surface working of each individual workpiece separately. This known solution weakness and deficiency are in the machine capacity limit depending on intermediate operations, the machine does not make the front surface profile working of different lengths and smaller intersections workpieces feasible, and further the working is also lagged behind provided the workpieces are twisted along the longitudinal and/or transversal axis, or otherwise deformed.
The solution pursuant to the international patent PCT/SE97/00234 is also known, whereby workpieces travel individually along the longitudinal conveyer with transverse leaning laths. Thereof, they further pass over to the next conveyer set up in the same direction, and which moves with a bit lower speed. Under both mentioned conveyors there is another, at an angle set third oblique conveyor with special lifting cranks at a fixed distance. In a certain moment each single crank leans under the workpiece that in a given moment travels on another conveyor to its area and is slowly lifting it, and in a defined moment overturns it on the other side. This known solution weakness and deficiency are in the fact that it is exclusively applicable for very flat workpieces of a very low quader form with a large area basic surface, and for low speeds, which all strongly decrease the machine capacity.
All the aforesaid known solutions common characteristics that simultaneously represent an outstanding problem in the profile both sides front surface working of optional lengths and intersections oblong workpieces are above all in working limitation of various intersections and lengths workpieces, in the working stroke procedure, unreliable clamping of workpieces during working, and likewise their conveying and turnover, possibility of frequent stoppages during working owing to deformed workpieces and machine damages in connection with it, as well as a relatively low capacity of these machines.
The technical problem being solved by the invention is such a machine construction that will enable simple and continuous front surfaces of oblong and a bit longer wood workpieces profile working, or production of toothed, key front surface joints on both ends of workpieces that will travel through in the flow sequence without intermediate stroke stops, or against adjacent working units, whereby they will rigidly be clamped inside clamping units on the longitudinal conveyors chain, while the position of workpieces before, during and after working will be adjusted by the entrance and exit turnover device and oblique roller conveyor.
According to the invention the problem is solved by the machine for profile working of front surfaces on oblong wood workpieces, essentially constructed of series and parallel set up conveyors, among which an entrance or exit turnover device is preferentially integrated in front of working units, whereby longitudinal conveyors are equipped with conveying chains upon which clamping units for clamping workpieces are fastened, and over them an oblique roller conveyor, and the oblique conveyor serves for redirecting workpieces from one to another row of conveyors. The invention will be more precisely described in a preferential feasibility example, which follows.